In repeated tests, scientists observed rats helping a fellow rat that was trapped, even when chocolate was served up as a tempting distraction. Of the 30 rats tested, 23 freed their fellow rodents. They even shared the goodies they could have gobbled on their own.

Rats' intelligence and biological similarities to humans have made them preferred lab subjects. Some people even adopt them as beloved pets.

But despite all their qualities, rats are generally synonymous with disease, dishonesty and dank sewers. They're depicted as bad guys in popular lore. And when has being called a rat ever been considered a compliment?

The rodents fare better in some global cultures. In the Chinese zodiac, for example, those born in the year of the rat are considered honest, creative and ambitious.

How do you feel about rats? Do you think they get a bad rap? Why or why not?